الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The present study is divided into four chapters:
Chapter (1): includes an introduction concerning the important role of analytical chemistry involving the immunoassay and chromatographic methods used for drugs analysis, and a brief account on the problem of drug abuse especially tramadol and diazepam.
Chapter (2): comprises the literature survey on the different methods used for the determination of tramadol hydrochloride, and diazepam these include chromatographic, spectrophotometer, and some other miscellaneous methods.
Chapter (3): includes the experimental part, the used materials, reagents, and preparation of solutions and method of extraction, UPLC-PDA method development, method validation parameters, and instruments. It also includes zinc sulphate adulteration in immunoassay.
Chapter (4): includes the results and discussion which is divided into three classes:
a- Includes the development and validation of UPLC-PDA method for simultaneous determination of tramadol and diazepam in human urine. This includes:
Summary
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I- UPLC-PDA method development which includes:
- Optimization of mobile phase using different parameters;
NaH2PO4 buffer concentration, pH values of NaH2PO4 buffer, wavelength and mobile phase.
- Optimization of extraction method.
II- UPLC-PDA method validation according to EMEA2011 guidelines includes: calibration curve (linearity), lower limit of detection (LOD), lower limit of quantitation (LOQ), recoveries, accuracy, (intra-day, inter-day) precision (repeatability), specificity, stability and robustness.
b- Immunoassay adulteration by Zinc sulphate in urine samples
This study focuses on the effects of zinc sulfate as a potential adulterant in urine drug testing. The effect of zinc sulfate on two drugs of abuse, tramadol and diazepam, was explored.
Tramadol and diazepam working solutions were prepared in plain urine samples separately to obtain three different concentrations of 100, 200 and 300 ng/ml for tramadol and 50, 70, 120 and 200 ng/ml for diazepam
(cutoff, lower and higher than cutoff). It is evident that urine samples containing zinc sulfate showed gradual decrease in concentration of either tramadol or diazepam relevant to zinc sulphate increasing concentration.
Drug-free urine was split into two separate tubes. To one of them, a zinc sulfate solution (10 mg/mL) was added. An absorption spectrum in the UV and visible range was then taken from the samples, both samples (with and without Zinc sulphate) showed almost the same U.V. spectrum.
c- Spot Tests for Detecting the Presence of Zinc
Sulfate in Urine
The first spot test is fairly specific for identifying zinc ion in urine because zinc ion has the unique feature of forming a white precipitate of zinc hydroxide in the presence of sodium hydroxide, which is soluble in excess sodium hydroxide. The second spot test consists of a yellow precipitate generated due to the formation of zinc chromate; this test is also specific for zinc because the other chromate salts that are insoluble in water have a much darker yellow color, although some chromate salts such as potassium chromate are water soluble and yellow.
Only lead was found to produce a false-positive result with the spot tests we developed. Fortunately, elevated blood lead levels are rare, occurring in approximately 6.3 per 100,000 adults. In addition, urine lead levels in adults with lead poisoning were reported to be significantly lower than the levels needed to cause a false-positive spot test in this investigation.